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排序方式: 共有961条查询结果,搜索用时 15 毫秒
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Reperfusion pulmonary edema 总被引:5,自引:0,他引:5
Reperfusion following lower-torso ischemia in humans leads to respiratory failure manifest by pulmonary hypertension, hypoxemia, and noncardiogenic pulmonary edema. The mechanism of injury has been studied in the sheep lung lymph preparation, where it has been demonstrated that the reperfusion resulting in pulmonary edema is due to an increase in microvascular permeability of the lung to protein. This respiratory failure caused by reperfusion appears to be an inflammatory reaction associated with intravascular release of the chemoattractants leukotriene B4 and thromboxane. Histological studies of the lung in experimental animals revealed significant accumulation of neutrophils but not platelets in alveolar capillaries. We conclude that thromboxane generated and released from the ischemic tissue is responsible for the transient pulmonary hypertension. Second, it is likely that the chemoattractants are responsible for leukosequestration, and, third, neutrophils, oxygen-derived free radicals, and thromboxane moderate the altered lung permeability. 相似文献
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N. Torlone A. Piazza M. Valeri P. I. Monaco L. Provenzani E. Poggi D. Adorno C. U. Casciani 《Transplant international》1992,5(Z1):S676-S678
Donor-specific anti-HLA antibodies were studied by cytotoxicity crossmatching (CTXM) and flow cytometry crossmatching (FCXM) in 117 kidney transplant candidates; the same study was carried out in 33 cadaver-donor kidney recipients, during the first 3 post-transplant months, for which donor cells were available. Pre-transport evaluation showed that 82.9 % of subjects were CTXM negative/FCXM negative, 6.8 % of patients were positive in both tests, and 10.3 % were CTXM negative/FCCM positive. Post-transplant monitoring for donor-specific antibodies (Abs-DS) showed that nine recipients (27.3 %) were FCXM positive; six of them were IgG + and three IgM +. In comparing these results with the clinical course, a significant association between FCXM IgG + and rejection episodes was observed (P < 0.01). 相似文献
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Disruption of cell polarity is seen in many cancers; however, it is generally considered a late event in tumor progression. Lethal giant larvae (Lgl) has been implicated in maintenance of cell polarity in Drosophila and cultured mammalian cells. We now show that loss of Lgl1 in mice results in formation of neuroepithelial rosette-like structures, similar to the neuroblastic rosettes in human primitive neuroectodermal tumors. The newborn Lgl1(-/-) pups develop severe hydrocephalus and die neonatally. A large proportion of Lgl1(-/-) neural progenitor cells fail to exit the cell cycle and differentiate, and, instead, continue to proliferate and die by apoptosis. Dividing Lgl1(-/-) cells are unable to asymmetrically localize the Notch inhibitor Numb, and the resulting failure of asymmetric cell divisions may be responsible for the hyperproliferation and the lack of differentiation. These results reveal a critical role for mammalian Lgl1 in regulating of proliferation, differentiation, and tissue organization and demonstrate a potential causative role of disruption of cell polarity in neoplastic transformation of neuroepithelial cells. 相似文献
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Charles R. Kiefer James B. McKenney Jane F. Trainor Richard W. Lambrecht Herbert L. Bonkovsky Lawrence M. Lifshitz C. Robert Valeri L. Michael Snyder 《The American journal of pathology》1998,153(3):703-708
To further the understanding of oxidative effects on inflammation injury to muscle fiber structure, fluorescent imaging analysis of human striated muscle tissues from a variety of inflammatory or postinflammatory etiologies was undertaken in a search for accumulated coproporphyrin, a red autofluorescent byproduct of heme biosynthesis that would theoretically be formed under oxidative insult. Using a differential excitation method of in situ analysis, porphyrin autofluorescence was detected in intact fibers within the context of the yellow autofluorescent subsarcolemmal lipofuscin granules. Relative measurements of porphyrin concentration in the granules from different patients indicated that the acute/subacute inflammatory specimens grouped significantly higher than the more chronic inflammatory and nonpathological specimens. Myoglobin was also found to be associated with the granules. Myoglobin heme iron could potentially serve as a Fenton reagent for the intracellular generation of hydroxyl radicals, which are responsible for the oxidation of the porphyrinogens. High-performance liquid chromatography analysis of extracted dense particles revealed coproporphyrin as the sole porphyrin present. The observation of coproporphyrin within lipofuscin granules, previously unreported, suggests that lipofuscin accumulation in striated muscle may begin under conditions of acute oxidative stress, as marked by the oxidation of extramitochondrial porphyrinogens that are immediately incorporated into the granules. 相似文献
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Bovicelli L Ghi T Pilu G Farina A Savelli L Simonazzi G Calzolari E Ferlini A Santini D Valeri B 《Human reproduction (Oxford, England)》2004,19(5):1231-1234
A complete mole coexisting with dichorionic twins was diagnosed by the combined use of sonography and chorionic villus sampling at 10 weeks gestation. The pregnancy resulted in the death of one fetus at 31 weeks from presumed feto-maternal haemorrhage, while the other fetus survived in good condition. A summary of the available literature, combined with this report, reveals a total of seven pregnancies with twins and a coexistent complete mole. Only two out of 14 fetuses survived. Maternal complications included one case of pre-eclampsia and one persistent trophoblastic tumour. Accurate diagnosis of complete mole is possible by genetic analysis of chorionic villi obtained with standard transabdominal sampling. Twins with a coexistent complete mole will usually undergo miscarriage. However, fetal survival is possible and the maternal risks seem limited. A concomitance between gestational trophoblastic disease and the occurrence of feto-maternal haemorrhage is observed. 相似文献
9.
Isaguliants MG Petrakova NV Mokhonov VV Pokrovskaya K Suzdaltzeva YG Krivonos AV Zaberezhny AD Garaev MM Smirnov VD Nordenfelt E 《Immunology letters》2003,88(1):1-13
Nonstructural protein 3 (NS3) of human hepatitis C virus (HCV) is a conserved multi-functional protein essential for replication and translation of viral RNA and polyprotein processing. Early T-cell response against NS3 is capable of restricting viremia. We aimed at characterizing the immunogenicity in gene immunization of the conserved regions of NS3 critical for protein folding and activity. C57BL/6 mice were injected with NS3 gene of Russian HCV 1b isolate 274933RU. Immunization did not exert any overt histological changes and had no long-term effects on the immune status of NS3 gene-recipients. The immune response in NS3 gene-recipients was screened by antibody ELISA, T-cell proliferation test and immune assays for specific cytokine production. T-lymphocytes of NS3 gene-recipients proliferated in response to peptides representing conserved regions of protease and ATPase/helicase. Stimulated T-lymphocytes produced IL-2, and in response to protease-derived peptides, also IFN-gamma. Potent and long-lasting antibody response was raised against conserved NS3 regions including "Greek-key" motif of protease, motifs II, V and polynucleotide-binding domains of ATPase/helicase. Thus, gene immunization effectively targeted conserved regions critical for NS3 protease and helicase function. In type and specificity, immune response of NS3 gene-immunized mice mimicked immunity achieved in the acute self-limiting HCV infection of human and primates and in virus-exposed healthy individuals, indicating promiscuity of NS3 as immunogen. 相似文献
10.
OBJECTIVE: To test the hypothesis that a supply of frozen red blood cells and a system for processing pyrogen-free crystalloid solution would meet the needs of an echelon 3 medical treatment facility in the U.S. military, caring for casualties during the initial phase of a military medical operation. DATA SOURCES: Blood requirements for potential combat casualties were estimated from transfusion data on: (1) patients admitted to Boston City Hospital following trauma, utilizing a computerized data base, (2) patients admitted to the Naval Support Hospital-Da Nang during the Vietnam War, from 1966 to 1970, from published and unpublished material, and (3) casualties estimated by Department of Defense expert panels for specific conflicts. The procedure for processing frozen red blood cells was evaluated at the Naval Blood Research Laboratory. Estimates of wounded in action were provided by the Department of Defense. DATA SYNTHESIS: Computer modeling using standard spreadsheet software on a personal computer. CONCLUSIONS: Under military conditions, a frozen red blood cell bank and a system for processing pyrogen-free resuscitative fluid could be used to prepare 96 units of red cells and 960 1 of crystalloid solution per day. This would be adequate to treat approximately 180 casualties, the number projected for a 5-day battle with heavy casualties (6 wounded in action/1,000 soldiers/day). It was concluded that a frozen blood bank system and system for processing pyrogen-free resuscitative fluid could successfully meet the needs of an echelon 3 medical facility in the initial phase of a military medical operation. 相似文献